A study examined the effectiveness of a writing center in improving student writing. All Composition 121 instructors except those who taught in the writing center were included. Students (1519 were enrolled in 69 sections of Composition 121) and instructors were randomly placed into three groups: Group I, the experimental group; Group II, the current practice group (business as usual); and Group III, the control group. The goal of Group I was to get students into the writing center as often as possible. The instructors of Group II encouraged their students to visit the writing center often, but did not require it. The instructors of Group III did not include anything about the writing center in their syllabi nor did they encourage their students to visit the center. All instructors in all three groups were asked to keep daily attendance records. Results indicated that the correlation between the grades in Composition 121 and the number of visits to the writing center seems statistically significant--the average grades were statistically significantly different between the group that visited the writing center and the one that did not. No D's or F's were reported from the group of students who attended the Writing Center 10 or more times. Also, of the total number of students who withdrew from Composition 121, more students were from the control group than the other two groups. A warning is issued, though, not to draw conclusions from the data because the results are not causal, only relational. Better students tend to be more persistent in seeking out assistance. Nevertheless, it looks like mandating attendance in the writing center does help. (Four pages of data, a writing center evaluation sample form, and a 16-item response summary are appended.) (CR)